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-rw-r--r--features/rt/locking-rtmutex-Use-custom-scheduling-function-for-s.patch242
1 files changed, 0 insertions, 242 deletions
diff --git a/features/rt/locking-rtmutex-Use-custom-scheduling-function-for-s.patch b/features/rt/locking-rtmutex-Use-custom-scheduling-function-for-s.patch
deleted file mode 100644
index 3ba23b2f..00000000
--- a/features/rt/locking-rtmutex-Use-custom-scheduling-function-for-s.patch
+++ /dev/null
@@ -1,242 +0,0 @@
-From 7e9de9093f6ab9c69a00c038c12e21054214f301 Mon Sep 17 00:00:00 2001
-From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
-Date: Tue, 6 Oct 2020 13:07:17 +0200
-Subject: [PATCH 082/191] locking/rtmutex: Use custom scheduling function for
- spin-schedule()
-
-PREEMPT_RT builds the rwsem, mutex, spinlock and rwlock typed locks on
-top of a rtmutex lock. While blocked task->pi_blocked_on is set
-(tsk_is_pi_blocked()) and task needs to schedule away while waiting.
-
-The schedule process must distinguish between blocking on a regular
-sleeping lock (rwsem and mutex) and a RT-only sleeping lock (spinlock
-and rwlock):
-- rwsem and mutex must flush block requests (blk_schedule_flush_plug())
- even if blocked on a lock. This can not deadlock because this also
- happens for non-RT.
- There should be a warning if the scheduling point is within a RCU read
- section.
-
-- spinlock and rwlock must not flush block requests. This will deadlock
- if the callback attempts to acquire a lock which is already acquired.
- Similarly to being preempted, there should be no warning if the
- scheduling point is within a RCU read section.
-
-Add preempt_schedule_lock() which is invoked if scheduling is required
-while blocking on a PREEMPT_RT-only sleeping lock.
-Remove tsk_is_pi_blocked() from the scheduler path which is no longer
-needed with the additional scheduler entry point.
-
-Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
----
- arch/arm64/include/asm/preempt.h | 3 +++
- arch/x86/include/asm/preempt.h | 3 +++
- include/asm-generic/preempt.h | 3 +++
- include/linux/sched/rt.h | 8 --------
- kernel/locking/rtmutex.c | 2 +-
- kernel/locking/rwlock-rt.c | 2 +-
- kernel/sched/core.c | 32 +++++++++++++++++++++-----------
- 7 files changed, 32 insertions(+), 21 deletions(-)
-
-diff --git a/arch/arm64/include/asm/preempt.h b/arch/arm64/include/asm/preempt.h
-index 80e946b2abee..f06a23898540 100644
---- a/arch/arm64/include/asm/preempt.h
-+++ b/arch/arm64/include/asm/preempt.h
-@@ -81,6 +81,9 @@ static inline bool should_resched(int preempt_offset)
-
- #ifdef CONFIG_PREEMPTION
- void preempt_schedule(void);
-+#ifdef CONFIG_PREEMPT_RT
-+void preempt_schedule_lock(void);
-+#endif
- #define __preempt_schedule() preempt_schedule()
- void preempt_schedule_notrace(void);
- #define __preempt_schedule_notrace() preempt_schedule_notrace()
-diff --git a/arch/x86/include/asm/preempt.h b/arch/x86/include/asm/preempt.h
-index f8cb8af4de5c..7e0358f99d22 100644
---- a/arch/x86/include/asm/preempt.h
-+++ b/arch/x86/include/asm/preempt.h
-@@ -104,6 +104,9 @@ static __always_inline bool should_resched(int preempt_offset)
- }
-
- #ifdef CONFIG_PREEMPTION
-+#ifdef CONFIG_PREEMPT_RT
-+ extern void preempt_schedule_lock(void);
-+#endif
-
- extern asmlinkage void preempt_schedule(void);
- extern asmlinkage void preempt_schedule_thunk(void);
-diff --git a/include/asm-generic/preempt.h b/include/asm-generic/preempt.h
-index d683f5e6d791..71c1535db56a 100644
---- a/include/asm-generic/preempt.h
-+++ b/include/asm-generic/preempt.h
-@@ -79,6 +79,9 @@ static __always_inline bool should_resched(int preempt_offset)
- }
-
- #ifdef CONFIG_PREEMPTION
-+#ifdef CONFIG_PREEMPT_RT
-+extern void preempt_schedule_lock(void);
-+#endif
- extern asmlinkage void preempt_schedule(void);
- #define __preempt_schedule() preempt_schedule()
- extern asmlinkage void preempt_schedule_notrace(void);
-diff --git a/include/linux/sched/rt.h b/include/linux/sched/rt.h
-index e5af028c08b4..994c25640e15 100644
---- a/include/linux/sched/rt.h
-+++ b/include/linux/sched/rt.h
-@@ -39,20 +39,12 @@ static inline struct task_struct *rt_mutex_get_top_task(struct task_struct *p)
- }
- extern void rt_mutex_setprio(struct task_struct *p, struct task_struct *pi_task);
- extern void rt_mutex_adjust_pi(struct task_struct *p);
--static inline bool tsk_is_pi_blocked(struct task_struct *tsk)
--{
-- return tsk->pi_blocked_on != NULL;
--}
- #else
- static inline struct task_struct *rt_mutex_get_top_task(struct task_struct *task)
- {
- return NULL;
- }
- # define rt_mutex_adjust_pi(p) do { } while (0)
--static inline bool tsk_is_pi_blocked(struct task_struct *tsk)
--{
-- return false;
--}
- #endif
-
- extern void normalize_rt_tasks(void);
-diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
-index 3fc947dd2e60..4cd9d6c4cd68 100644
---- a/kernel/locking/rtmutex.c
-+++ b/kernel/locking/rtmutex.c
-@@ -1049,7 +1049,7 @@ void __sched rt_spin_lock_slowlock_locked(struct rt_mutex *lock,
- raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
-
- if (top_waiter != waiter || adaptive_wait(lock, lock_owner))
-- schedule();
-+ preempt_schedule_lock();
-
- raw_spin_lock_irqsave(&lock->wait_lock, flags);
-
-diff --git a/kernel/locking/rwlock-rt.c b/kernel/locking/rwlock-rt.c
-index 64c4f5728b11..948d10214ee2 100644
---- a/kernel/locking/rwlock-rt.c
-+++ b/kernel/locking/rwlock-rt.c
-@@ -211,7 +211,7 @@ static void __write_rt_lock(struct rt_rw_lock *lock)
- raw_spin_unlock_irqrestore(&m->wait_lock, flags);
-
- if (atomic_read(&lock->readers) != 0)
-- schedule();
-+ preempt_schedule_lock();
-
- raw_spin_lock_irqsave(&m->wait_lock, flags);
-
-diff --git a/kernel/sched/core.c b/kernel/sched/core.c
-index 46e7db92b343..59fb8b18799f 100644
---- a/kernel/sched/core.c
-+++ b/kernel/sched/core.c
-@@ -5004,7 +5004,7 @@ pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
- *
- * WARNING: must be called with preemption disabled!
- */
--static void __sched notrace __schedule(bool preempt)
-+static void __sched notrace __schedule(bool preempt, bool spinning_lock)
- {
- struct task_struct *prev, *next;
- unsigned long *switch_count;
-@@ -5057,7 +5057,7 @@ static void __sched notrace __schedule(bool preempt)
- * - ptrace_{,un}freeze_traced() can change ->state underneath us.
- */
- prev_state = prev->state;
-- if (!preempt && prev_state) {
-+ if ((!preempt || spinning_lock) && prev_state) {
- if (signal_pending_state(prev_state, prev)) {
- prev->state = TASK_RUNNING;
- } else {
-@@ -5141,7 +5141,7 @@ void __noreturn do_task_dead(void)
- /* Tell freezer to ignore us: */
- current->flags |= PF_NOFREEZE;
-
-- __schedule(false);
-+ __schedule(false, false);
- BUG();
-
- /* Avoid "noreturn function does return" - but don't continue if BUG() is a NOP: */
-@@ -5174,9 +5174,6 @@ static inline void sched_submit_work(struct task_struct *tsk)
- preempt_enable_no_resched();
- }
-
-- if (tsk_is_pi_blocked(tsk))
-- return;
--
- /*
- * If we are going to sleep and we have plugged IO queued,
- * make sure to submit it to avoid deadlocks.
-@@ -5202,7 +5199,7 @@ asmlinkage __visible void __sched schedule(void)
- sched_submit_work(tsk);
- do {
- preempt_disable();
-- __schedule(false);
-+ __schedule(false, false);
- sched_preempt_enable_no_resched();
- } while (need_resched());
- sched_update_worker(tsk);
-@@ -5230,7 +5227,7 @@ void __sched schedule_idle(void)
- */
- WARN_ON_ONCE(current->state);
- do {
-- __schedule(false);
-+ __schedule(false, false);
- } while (need_resched());
- }
-
-@@ -5283,7 +5280,7 @@ static void __sched notrace preempt_schedule_common(void)
- */
- preempt_disable_notrace();
- preempt_latency_start(1);
-- __schedule(true);
-+ __schedule(true, false);
- preempt_latency_stop(1);
- preempt_enable_no_resched_notrace();
-
-@@ -5313,6 +5310,19 @@ asmlinkage __visible void __sched notrace preempt_schedule(void)
- NOKPROBE_SYMBOL(preempt_schedule);
- EXPORT_SYMBOL(preempt_schedule);
-
-+#ifdef CONFIG_PREEMPT_RT
-+void __sched notrace preempt_schedule_lock(void)
-+{
-+ do {
-+ preempt_disable();
-+ __schedule(true, true);
-+ sched_preempt_enable_no_resched();
-+ } while (need_resched());
-+}
-+NOKPROBE_SYMBOL(preempt_schedule_lock);
-+EXPORT_SYMBOL(preempt_schedule_lock);
-+#endif
-+
- #ifdef CONFIG_PREEMPT_DYNAMIC
- DEFINE_STATIC_CALL(preempt_schedule, __preempt_schedule_func);
- EXPORT_STATIC_CALL_TRAMP(preempt_schedule);
-@@ -5362,7 +5372,7 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void)
- * an infinite recursion.
- */
- prev_ctx = exception_enter();
-- __schedule(true);
-+ __schedule(true, false);
- exception_exit(prev_ctx);
-
- preempt_latency_stop(1);
-@@ -5580,7 +5590,7 @@ asmlinkage __visible void __sched preempt_schedule_irq(void)
- do {
- preempt_disable();
- local_irq_enable();
-- __schedule(true);
-+ __schedule(true, false);
- local_irq_disable();
- sched_preempt_enable_no_resched();
- } while (need_resched());
---
-2.19.1
-
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-05-05 21:46:24 +0000